Density = mass / volume
Because the dimensions of the barometer are the same for each case, we can compare the heights of the liquids instead of the volume.
ρ(mercury) = 13.6ρ(water)
mass(mercury)/760 = 13.6 x mass(water)/Height(water)
Masses of the liquids will also be the same.
Height of water = 13.6 x 760
Height of water = 10,336 mm
Answer:
Explanation
Comment
Normally you would just use m*c*delta T. But the c is the same in both cases, so you need just use m*deltaT
Givens
25 degrees
m = ?
T = 25
t = final temp = 75
93 degrees
m = 250
T = 93
t = final temp = 75
Solution
(t - 25)*m = (93 - t) * 250 Remove the brackets
75*m - 25m = 93*250 - 250*75 Combine the right
m(75 - 25) = 23250 - 250*75
50 m = 23250 - 18750 Combine
50 m = 4500 Divide both sides by 50
50*m/50 = 4500/50
m = 90
Answer: 90 grams are needed.
C because it is the highest frequency jk idk I’m just doin it for the sign up think
<span>this is a limiting reagent problem.
first, balance the equation
4Na+ O2 ---> 2Na2O
use both the mass of Na and mass of O2 to figure out how much possible Na2O you could make.
start with Na and go to grams of Na2O
55.3 gNa x (1molNa/23.0gNa) x (2 molNa2O/4 molNa) x (62.0gNa2O/1molNa2O) = 75.5 gNa2O
do the same with O2
64.3 gO2 x (1 molO2/32.0gO2) x (2 molNa2O/1 mol O2) x (62.0gNa2O/1molNa2O) = 249.2 g Na2O
now you must pick the least amount of Na2O for the one that you actually get in the reaction. This is because you have to have both reacts still present for a reaction to occur. So after the Na runs out when it makes 75.5 gNa2O with O2, the reaction stops.
So, the mass of sodium oxide is
75.5 g</span>
Answer:
Percent error = -4.7%
Explanation:
Given data:
Actual density value = 19.3 g/cm³
Measured value of density by student = 18.4 g/cm³
Percent error = ?
Solution:
Formula:
Percent error = ( measured value - actual value / actual value ) × 100
Now we will put the values.
Percent error = ( 18.4 g/cm³ - 19.3 g/cm³ / 19.3 g/cm³) × 100
Percent error = (-0.9 g/cm³ / 19.3 g/cm³) × 100
Percent error = -0.047 × 100
Percent error = -4.7%
Negative sign shows that measured value is less than actual value.
